|
  |
|
|
Pinhole Cameras
Technically, a camera does not need a lens, as witness the very healthy community of pinhole camera suppliers and enthusiasts. A pinhole camera uses an extremely small hole in a very thin material to focus light. They rely on extremely small apertures (about a 1/100 or less of the distance to the screen on which the image is to be projected) to obtain a clear image. The "cleaner" the hole and the thinner the material, the sharper the image. Laser cut holes in thin metal produce excellent pictures. Pinhole cameras do not generally have a traditional shutter; the tiny aperture leads to exposures measured in seconds, hours or even days, so it is enough to cover and uncover the pinhole by hand, much as was done with early plate cameras.
The pinhole camera shares other characteristics with early plate cameras: the image is projected upside down, and can only be viewed in the dark. No bright image viewfinders here. Images from high precision pinhole cameras have extreme depth of field. Originally projected against a wall in a dark room (the Camera Obscura, or ‘dark chamber’ from which we derive the word 'camera'), it is now more usual to use a translucent screen for real-time viewing (a safe way to observe solar eclipses). Many enthusiasts fit their pinhole cameras with film carriages and CCD sensors(charge coupled device) as used in digital cameras, and such CCD equipped cameras have found a commercial use in surveillance work because of their small size and the fact that not having a lens make them much less obviously cameras. |
|
 |
|
PLEASE VISIT THE CONTRIBUTOR'S WEBSITE
No reactions yet.
Please login or sign up to rate this intel.
Please login or sign up to add a comment.
The copyright for this content entitled "Pinhole Cameras" has been specified by the contributor as:
All Rights Reserved
This content may not be copied, distributed or adapted by anyone under any circumstances.
|
|
|
This intel was contributed by David Rich
David Rich
|
May, 2012
2008
January, February, March, April, May, June, July, August, September, October, November, December
2009
January, February, March, April, May, June, July, August, September, October, November, December
2010
January, February, March, April, May, June, July, August, September, October, November, December
2011
January, February, March, April, May, June, July, August, September, October, November, December
2012
January, February, March, April, May
|
|
Not a member yet?
Qondio is a powerful network for making it online. If you have a website to
promote, we can help.
Sign up and get in on the action.
|
|
Welcome to Qondio! Discover the awesome power this network can deliver by going to our About page. Or you could skip straight to the Sign Up form.
|
|
